Hydraulic aggregates of this type are known; see, for example, DE 10 2004 032 256 B3. Such aggregates are used as compact units in various types of conveyor and hoisting gear for actuation of lifting cylinders. The pertinent hydraulic pump is conventionally driven by an electric motor, especially for nonstationary applications, for example, in the actuation of loading platforms. Direct current motors are used which can be operated in a power class of about 0.8 kW to 3.0 kW from the pertinent on-board network.
As a result of the diverse fields of application and the resulting different installation situations, such hydraulic aggregates are conventionally implemented in various design concepts. Fundamental differences exist, especially between versions for installation with a vertical major axis and versions for horizontal installation.